Like all trimesters of pregnancy, the third and final one comes with its own share of significant changes.
Most of them have to do with increased size and weight. After all, your baby grows from around two pounds at the end of the second trimester to a whopping six to nine pounds on average.
Also, as Sara Haley, ACE-certified pre- and postnatal exercise specialist and mom of three, explains, the expanding size of the uterus in this trimester places pressure on the abdominal wall.
This pressure can sometimes cause the abdominals to separate too much (known as diastasis recti). This can make recovery in the fourth trimester (aka postpartum) a bit more challenging.
Whether you’re an avid exerciser or an occasional gym goer, you’ll want to take precautions to adjust to the changes.
Make sure you follow a safe and effective program that suits your needs as an expectant mom.
To help you navigate fitness safely in your third trimester, we asked top experts to share the important ways that exercise should change and what moms-to-be should know.
Avoid any exercises performed on your back
Some pregnant women can get away with doing back-lying exercises well into the second trimester.
The weight of their baby is not yet heavy enough to place restricting pressure on their inferior vena cava. (This is the large vein that carries oxygen to the heart.)
However, by the third trimester all women should stop doing any exercise performed in a supine (back) position.
“In the third trimester, the baby is heavy enough to compress that vein, which, especially after long periods of time, can cause negative symptoms for both mom and baby,” says Kendall Janicola, certified personal trainer and instructor at Fhitting Room in New York City.
Or you can give your body a break and relax your mind. Check out the meditation classes in the Aaptiv app today.
Take it down another notch, if needed
Some of the biggest shifts in late pregnancy occur in the cardiovascular system.
“By the middle of the third trimester, blood volume has increased by 40-50 percent to allow the developing fetus to have access to more oxygen, vitamins, and minerals,” explains Tara Allen, RN, women’s health nurse, personal trainer, health coach, and nutritionist.
“For the mother, this means a faster heart rate and more challenging rate of perceived effort (she’ll get out of breath faster).”
Also, as a result of an increase of blood volume, iron stores become diluted. This can result in anemia that can further leave a mom-to-be feeling fatigued and winded much earlier in her exercise routine than usual.
Avoid intense ab workouts
Unless you pride yourself on your super strong core, Janicola recommends avoiding exercises in a plank position, as well as abdominal crunches.
“As the belly gets bigger and protrudes more in the third trimester, it is common for there to be some separation of the rectus abdominis, which runs vertically down the center of the abdomen,” she says.
“This separation, termed ‘diastasis recti,’ can occur in degrees, so it’s best not to risk this in the third trimester.”
Enlist the help of a spotter
Floor movements, like squats, are encouraged for pregnant women.
However, they can become increasingly difficult in the third trimester, when your balance is off-kilter. For this reason, Janicola suggests asking someone to spot you.
“Your center of gravity will probably feel different than it did in the first or second trimester. Holding onto something or someone can be helpful in keeping this excellent move safe,” she says.
“If there’s a partner available, each person can grasp the forearms of the other as they squat together.”
Up the ante on pelvic exercises
By the time you reach your third trimester, you should start integrating pelvic exercises, like kegels, into your routine.
“Kegel exercises, where the pelvic floor muscles are contracted and released, will help tone the internal part of the body responsible for decreasing stress incontinence (due, at this point in time, to the weight of the baby, placenta, and fluid),” explains Janicola.
“Toned, strong pelvic floor muscles will also play a very helpful role during the pushing stage of labor.”
Avoid exercises that involve jumping
Exercises that involve jumping are best to avoid in the third trimester for some obvious, and not-so-obvious reasons.
“Jumping can be a seriously uncomfortable movement with about 12 pounds of baby, placenta, and amniotic fluid tightly concentrated in the center of one’s body,” says Janicola.
“Internally, the loose ligaments, caused by the hormone ‘relaxin,’ are more prone to injury.” Walking, jogging, prenatal yoga, and swimming are better options for a mom-to-be in trimester three.
For exercises you can do while pregnant, check out Aaptiv. We have stretching, meditation and more.